Process of manufacturing coke



(No Model.)

H. M. PIERCE.

PROCESS OF MANUFACTURING 00KB.

No. 330,731. Patented Nov. 17, 1885";

IlNrrnn Snares Farnmr @rricn.

HENRY M. PIERCE, OF EASHVILLE, TENNESSEE.

PROCESS OF MANUFACTURING COKE.-

SPECIFICATION forming part of Letters Patent No. 330,731, dated November17, 1885.

Application filed July 31, 1884.

To all whom it may concern:

Be it known that I, HENRY M. PIERCE, a citizen of the United States,residing at Nashville, in the county of Davidson and State of Tennessee,have invented certain new and useful Improvements in Processes ofManufacturing Coke; and I hereby declare the following to be a full,clear, and exact description of the same, reference being had to theaccompanying drawings, which form a part of this specification, showingthe preferred means adapted to carry out the method.

The method commonly practiced in this country for the manufacture ofcoke consists in the use of small mound-shaped ovens about ten (10) feetin diameter at the base, and adapted to hold a charge of about four (4)tons, or one hundred (100) bushels. The firing is done at the top andthe coking process proceeds fromabove' downward, first supported bycombustion of the upper layer of coal, and afterward by the volatilematter and gases evolved from the deeper layers, and which becomesignited and burns in the upper or vacant portion of the oven. The air tosupport combustion is admitted in limited quantities by means of portsor around the top of the coke-oven door. The difficulties encountered bythis method are, first, loss from the per cent. of coal consumed in theearly stages of the process; secondly, loss from the imperfectly-cokedmass which remains in the oven; thirdly, the loss from or waste of thelarge percentage of the heatingpower of the volatile matters, gases,&c., which burn in the upper part of the oven and as a result thereof;fourthly, the unequal heating of the oven, and the unnecessarily slowprogress of the coking.

To avoid the cost entailed by the use of small 0vens,,and in a measurethe loss from the imperfectly-coked mass remaining in the bottom of theovens, large kilns open at the top have been employed, and the cokingprocess con ducted by cross-firing and by proceeding from below upward,for which purposes a series of horizontal air and draft flues wereconstructed in the bottom ofthe charge; but by this method, though thelimitation of the charge was avoided, the loss from consumed coal stillresulted, and the loss of the heating value of the gas and volatileproducts was augmented.

A third mode of procedure has been to em- Serial No. 139,263. (Nomodel.)

ploy a series of vertical retorts surrounded by combustion-fines whereinthe gas evolved from the cokingcharge was burned to heat the retort andperform the coking. By this means, while the heating value of theevolved gas, &c., was saved, the capacity of the oven and plant waslimited with all its attendant cost and disadvantages, save the unequalheating of the charge.

Having above pointed out the methods commonly practiced and the meansemployed, I will now first indicategenerally the character of myinvention, and then describe specifically the best manner now known tome of carrying it into effect. Its objects are to avoid loss of fuel bydirect combustion of any portion of the charge, therefore I conduct theprocess by radiated heat; secondly, to utilize all the heating value ofthe evolved gases, consequently I utilize said gases as the fuel forproducing the heat to heat the whole charge uniformly, and at thesametime avoid the deposit of tarry matter and the formation of animperfectly-coked mass at the bottom of the charge and the attendantloss, so I apply the radiated heat at the bottom of the charge; and,finally, to avoid limiting the size of the charge to be treated, andthis results as a sequence of applying the heat at the bottom of thecharge. Therefore the method may be generally stated as conducting thecoking process by means of radiated heat applied to the base or bottomof the charge or mass, said heat being produced by the combustion of thevolatile vapors and gases evolved from the charge during the cokingprocess.

I will next describe the apparatus which I have devised for the purpose.

In the drawings, Figure 1 is a perspective view of a battery of severalcoke-ovens, constituting a plant or works. Fig. 2 is a verticallongitudinal section of an oven and its appurtenances. Fig. 3 is ahorizontal section on the line :20 m, Fig. 2, showing the charge orcoking chamber. Fig. 4 is a similar section on the line y 3 Fig. 2,showing the main combustion-chamber and radiating or branchcombustion-chamber.

Like letters refer to like parts wherever they occur.

A A A indicate a series of ovensof like character arranged in battery.Each oven is and injectors ofthe combustible gases.

by preference of a rectangular or.quadrilateral form, having its outerwalls of brick or stone,with a lining of fire-brick, if preferred, and,if found necessary, a packing or deadair space between the outer walland lining, as in constructing some classes of .blast-furnaces. In sizeit generally exceeds an ordinary cokeov'en, havinga capacity of, say,from forty to sixty tons, being practically limited only by theconvenience of the manufacture. At the bottom, andextendinglongitudinally, (and preferably centrally fromend to end,) isan arched fiue,tunnel, or combustion-chamber, B, from which at shortintervals extend transverse branches 1;, which terminate in lateralcollecting-fines 0, leading. tosuitable chim neys, c. The numberandarrangement of the branches 1) will be such as to form, practically,a hollow hearth or bottom for thewholeoven. The chimneys may be oftriangular formand occupy the corners of the oven, thussaving space andgiving to theoven an interiorform, which facilitates the withdrawal ofthe coke.

Directly over the combustion-chamberB and its branches 1) is laid theiioor of the coking chamber. At each end of the oven A are two or moredoors, a a, through which the oven may be charged and the coke withdrawnwhen the coking process is finished, and separating the doors oroccupying the space between the same at each end of the oven: issituated a chambcigalso of triangular cross-section, and forming adead-air space extending from the floor to the roof of thecokingchamber.

It will be observedthat the triangular form of the chimneys c andchamber 0 economizes space, and at the same time frees theioven ofcorners or pockets, which: might. not be read ily accessible whenremoving the coke. :Each chimney may be provided witha steam-jet toinduce a draft thereth rough when desired.

In the crown orarch of the ovenare twoor more gas-ports, a, which may bealso usedas charging-ports for introducing coal when desired. Theseports are provided withstoppers for closing thesame when not in use.

In the end walls of the oven,just, below the crown or arch, one or moreat-each end, are gas-pipes cl, provided with valves d anddelivering intoa receiving-main, D. ;In this pipe (1, just beyond the valve 61, isarranged a steam-jet, e, which may besupplied with steam from anysuitable source; and. extending from the receiving-main D atapointopposite the pipe (1 is a valved cross-pipe,, d which connects witha delivery-maimE, from which a branch gas-pipe, (i provided with asteam-jet, projects into the. combustion-chamber B. The function of thesteam-jets in the pipes d and d is respectively to act as ejectors Thisconstruction is preferably applied to each end of the furnace, as shownin Fig.2, so that the heat may be uniformly distributedathrough thepassages 12.

hen asingle oven A is employed, the receiving-main D and delivery main Emay be dispensed with, and the pipes d d? d may be consolidated andhavebut a single steam jet and valve.

The above description, which has been limited to a single oven, is to beunderstood as applying to each oven of the series shown.

I will next describe the arrangement and connection of ovens when aseries or plant is employed.

Any number of ovens A, according to the size of the ovens and thecapacity of the desired-works, are arranged in line in j uxtaposition,and the gas exits or pipes cl of each oven are connected withreceivingmains D, which extend the length of the battery. There are alsodelivery-mains E (one for each side of the battery, as is theqcase of:the receivingmains D) extending the length of the battery parallel withand below the receiving-mains, and thesemainsoare connected withthegaspipes 01 .Where thevolatile vapors and gases evolved from thecokingcoal are to be used in the condition in which theycome from the ovens,the receiving-mains D may be connected directlywiththe delivery-mainsEby the bypathsFalone; but as it is sometimes desirable to eliminatefrom the gases evolved in the oven the ammonia, &c., a condenser orscrubber, Gr, may be interposed between the receiving-main D and the:deliv-ery-mainE, so that the gas, .&c., can be :used innaturalconditionor after treatment, as preferred.

The devices being substantially of the character' hereinbeforespecified, the process will be conducted as follows: The ovens are dulycharged with the coal toxbe coked, and where the plant is first ororiginally put in operation the charge is heated. by radiated heat froma fire kindled in the combustion-chamber B,

. thesgas-ports aare opened, and, the fire being urged, the vapors,gases, 8rd, are permitted to escape at 0/ until they are found to be ofi an inflammable character. When this occurs, the va-lvesdofpipes d areopened and the ports a closed, which permits-the evolved gases,v&c.,.toenter the receiving-main D. Jet 6 may then be started, (thevalvein crosspipe d being' open,).and the gas forced .directly fromthe oventhrough pipes d d d into. the combustion-chamber B, (at each end'of.the..oven,).where, being ignited, it. burns, developing-an intenseheat, which is distributeduthrough. the-various branch flues b under.the whole coking-chamber, and radiates: intothe. base thereof, the gasesevolved from 1 the charge serving to convey the heat into the upperlayers thereof, so that the coking process progresses upward from 1below rapidly and uniformly until the whole charge iscoked. Toward 'theclose of the coking process, if it is desired to expedite matters andinsure the perfect coking of the: upper layer, the steam-jet e .anddamper d in pipe d may ,beclosed so as to. out off the voven from thereceiving-mainD. The portsa may be then opened, and the gas remaining.in' the top or upper part of the .kiln may be ignited therein,

so as to apply a more direct and immediate heat to the upper layer ofthe charge; or where the ovens are worked in batteries, as shown in Fig.1, the valves of the cross-pieces d may be closed, and the gas, afterentering the receiving-main D, may pass the length thereof and intodelivery-mains E, either directly by the by-paths F or after passingthrough the condensers, scrubbers, &c., at G.

As each chimney c is provided, with a steam-jet and a damper, (which arenot shown, as they can be of any common and well-known character,) incase the coking should be progressing more rapidly at one part of thecoking-chamber than at another, the jets can be temporarily turned offand the chimneys closed on that side or portion, and the whole or largerpart of the heating-flame turned under that portion of thecoking-chamber where the process is progressing more slowly, and thusthe balance or equilibrium can be restored. This advantage is one of theincidents of heating by radiation through baseflues of the generalcharacter specified.

As the various pipes and mains d, d (P, D,

and E are provided with suitable valves,

steam jets, and connections, as hereinbefore specified, it is apparentthat any one or more of the ovens can be cut out of the series when itis to be charged or the coke withdrawn; that when the battery has oncebeen put in operation that operation can be continuously maintainedwithout other fuel than the gas evolved from the coal in the cokingprocess, and that any oven may be heated either by the gas evolvedtherein or by gas from the other ovens of a battery, and consequentlythe ovens, though arranged in battery, may be operated independently.

I do not herein claim the apparatus described, as the same is made thesubject-matter of a separate case, Serial No. 160,933, filed April 1,1885.

Having thus set forth the nature, advantages, and operation of myinvention, what I claim, and desire to secure by Letters Patent,

1. As an improvement in the manufacture of coke, the method ofconducting the furnace operation which consists in first carrying on thecoking process by radiated heat until a stage near the completion of theprocess, and then firing the evolved gas in the chamber above the chargeand completing the coking by the heat therefrom, substantially as andfor the purposes set forth.

2. As an improvement in the art of manufacturing coke, the method ofconducting the furnace operation which consists in heating the charge byradiation until inflammable gases are given off, then leading said gasesbeneath the floor of the coking-chamber and burning them therein,thereby coking the under layers of the charge by radiated heat, andfinally shutting off the flow of gases to the under combustion-chamberand burning them in the top of the kiln, thereby coking the top layersof the charge by direct heat, substantially as described.

In testimony whereof I have affixed my sig nature, in presence of twowitnesses, this 28th day of July, 1884.

HENRY M. PIERCE.

Witnesses:

R. W. BAGOT, STEWART CHURCH.

